refactor

lib/file/default.nix

@@ -0,0 +1,25 @@
+{ lib, ... }:
+
+rec {
+  ## Append text to the contents of a file
+  ##
+  ## ```nix
+  ## fileWithText ./some.txt "appended text"
+  ## ```
+  ##
+  #@ Path -> String -> String
+  fileWithText = file: text: ''
+    ${builtins.readFile file}
+    ${text}'';
+
+  ## Prepend text to the contents of a file
+  ##
+  ## ```nix
+  ## fileWithText' ./some.txt "prepended text"
+  ## ```
+  ##
+  #@ Path -> String -> String
+  fileWithText' = file: text: ''
+    ${text}
+    ${builtins.readFile file}'';
+}